Power semiconductor device module having mechanical corner press-fit anchors

ABSTRACT

A power semiconductor device module includes a metal baseplate and a plastic housing that together form a tray. Power electronics are disposed in the tray. A plastic cap covers the tray. Electrical press-fit terminals are disposed along the periphery of the tray. Each electrical terminal has a press-fit pin portion that sticks up through a hole in the cap. In addition, the module includes four mechanical corner press-fit anchors disposed outside the tray. One end of each anchor is embedded into the housing. The other end is an upwardly extending press-fit pin portion. The module is manufactured and sold with the press-fit pin portions of the electrical terminals and the mechanical corner anchors unattached to any printed circuit board (PCB). The mechanical anchors help to secure the module to a printed circuit board. Due to the anchors, screws or bolts are not needed to hold the module to the PCB.

CROSS REFERENCE TO RELATED APPLICATION

This application is a continuation-in-part of, and claims priority under35 U.S.C. § 120 from, nonprovisional U.S. patent application Ser. No.15/143,575 entitled “Power Semiconductor Device Module Having MechanicalCorner Press-Fit Anchors,” filed on Apr. 30, 2016. The entire subjectmatter of application Ser. No. 15/143,575 is incorporated herein byreference.

TECHNICAL FIELD

The described embodiments relate to power semiconductor device modules.

BACKGROUND INFORMATION

FIG. 7 (Prior Art) is a perspective diagram of a common type ofconventional power semiconductor device module 100. The four holes101-104 are used to screw or bolt or otherwise attach the module 100 toa heatsink (not shown) so that the planar bottom side of the module isin good thermal contact with a planar surface of the heatsink. There arepress-fit pins that are shown extending upward from the top of themodule 100. One of these press-fit pins is labeled 105 in theillustration. These press-fit pins are pressed into corresponding holesin a printed circuit board (not shown). The printed circuit board (PCB)is typically a PCB that has other circuitry and other circuit componentsmounted on it. That other circuitry and the other circuit componentstogether form a larger power circuit and device of some sort thatincludes the module 100. After the module 100 has been press-fit to thePCB as is done in the prior art, screws or bolts may be optionallyscrewed down through holes in the PCB and into corresponding mountingholes 106-109 in the housing frame 110 of the module. These screws orbolts provide additional mechanical strength to the connection betweenthe module and the PCB. Module 100 is a common and commerciallysuccessful type of power semiconductor device module.

SUMMARY

A power semiconductor device module includes a metal baseplate and aplastic housing that together form a shallow tray. The plastic housingmay be glued to or otherwise engage the metal baseplate so that theshallow tray is formed. Power electronic circuitry is disposed in thetray under a layer of encapsulant, such as silicone gel. A plastic capcovers the tray so as to enclose the power electronics and the siliconelayer within a shallow housing. A plurality of electrical press-fitterminals is disposed along the periphery of the tray. Each electricalpress-fit terminal has a lower portion and an upper portion. The lowerportion in one example includes a laterally-extending landing pad. Thelower portion slides into, and is held in place by, a channel on aninner sidewall of the tray. The electronics in the tray is then coupled,for example by a wire bond, to this landing pad portion. The upperportion of each electrical press-fit terminal is a press-fit pinportion. The press-fit pin portion of each electrical press-fit terminalsticks up through a corresponding hole in the cap and extends away fromthe top of the cap in a direction that is perpendicular to the plane ofthe bottom surface of the metal baseplate. In addition, the powersemiconductor device module includes four novel mechanical cornerpress-fit anchors. When the power semiconductor device module isconsidered from the top-down perspective, these four mechanical cornerpress-fit anchors are disposed outside the confines of the rectangulartray area. There is one such mechanical corner press-fit anchor locatedadjacent each corner of the power semiconductor device module when themodule is considered from the top-down perspective. Each of the fourmechanical corner press-fit anchors has one end that is secured into thehousing of the module, and has another end that is an upwardly extendingpress-fit pin portion.

The power semiconductor device module is manufactured and sold in thisway, with the press-fit pin portions of the electrical terminals andwith the press-fit pin portions of the mechanical corner anchors inplace as part of the module, but with all the press-fit pin portionsbeing unattached to any PCB. During press-fit mounting of the module,when the press-fit pin portions at the top of the module are forced intocorresponding holes in a PCB, the mechanical anchors help mechanicallysecure the module to the PCB. Due to the mechanical corner press-fitanchors, screws or bolts that are sometimes otherwise provided in orderto hold the module to the PCB are not needed and are not provided. Inone example, a mechanical corner press-fit anchor has a barb or a catch.This barb or catch helps secure the anchor into the plastic of thehousing. Due to the barb or catch, a substantial pull force can be puton the anchor without the anchor moving back upward and out of the hole.The mechanical corner press-fit anchors, when they are press-fitattached to a PCB, allow the module to resist and withstand substantialpull out forces without moving away from the PCB. The use of themechanical corner press-fit anchors allows mechanical stresses andwarpage problems associated with hold-down screws or bolts to beavoided. Costs and delays and complexities involved in installing thehold-down screws or bolts are also avoided.

Further details and embodiments and techniques are described in thedetailed description below. This summary does not purport to define theinvention. The invention is defined by the claims.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, where like numerals indicate like components,illustrate embodiments of the invention.

FIG. 1 is a top-down perspective diagram of a power semiconductor devicemodule in accordance with one novel aspect.

FIG. 2 is a side view of the power semiconductor device module of FIG.1.

FIG. 3 is a top-down view of the power semiconductor device module ofFIG. 1.

FIG. 4 is a diagram of one example of a mechanical corner press-fitanchor.

FIG. 5A is a diagram of a first example of an electrical press-fitterminal.

FIG. 5B is a diagram of a second example of an electrical press-fitterminal.

FIG. 5C is a diagram of a third example of an electrical press-fitterminal.

FIG. 6 is a side view of an assembly involving the power semiconductordevice module of FIG. 1 press-fit to a PCB and bolted to a heatsink. Theareas of the bolts 69 and 70 are shown in cross-section.

FIG. 7 (Prior Art) is a perspective diagram of one type of conventionalpower semiconductor device module.

DETAILED DESCRIPTION

Reference will now be made in detail to a background example and to someembodiments of the invention, examples of which are illustrated in theaccompanying drawings. In the description and claims below, when a firstobject is referred to as being disposed “over” or “on” or “onto” asecond object, it is to be understood that the first object can bedirectly on the second object, or an intervening object may be presentbetween the first and second objects. Similarly, terms such as “upper”,“top”, “up”, “down”, “vertically”, “horizontally”, “laterally”, “lower”,“under”, “below”, “beneath” and “bottom” are used herein to describerelative orientations between different parts of the structure beingdescribed, and it is to be understood that the overall structure beingdescribed can actually be oriented in any way in three-dimensionalspace.

FIG. 1 is a top-down perspective diagram of a power semiconductor devicemodule 1 in accordance with one novel aspect. FIG. 2 is a side view ofthe power semiconductor device module 1 of FIG. 1. FIG. 3 is a top-downview of the power semiconductor device module 1 of FIG. 1.

The power semiconductor device module 1, when considered from thetop-down perspective, has a bottom surface and a top surface. The powersemiconductor device module 1 includes an injection molded plastichousing frame 2 that along with a metal baseplate 3 forms a centralshallow tray-shaped recess or depression. The plastic housing frame 2extends around and frames the metal baseplate 3. The metal baseplate 3forms the bottom of the tray. The plastic housing frame 2 forms thesidewalls of the tray. The shallow tray portion of the plastic housingframe 2 has an upper rim.

The metal baseplate 3 has a planar bottom surface that is a part of thebottom surface of the overall power semiconductor device module 1. Theplanar bottom surface may be perfectly planar or may be very slightlyconvex-curved. The term “convex” here in the side view perspective ofthe diagram of FIG. 2 means that the center portion of the bottomsurface of the baseplate 3 bows down a bit as compared to the bottomsurface of the baseplate 3 at left and right sides of the baseplate. Theamount of convex bow is determined by the amount of force with which themodule is to be held against a planar heatsink surface, and may dependon various factors including the number and size of hold down bolts, thetype and size and shape of the heatsink, and the surface area of thebottom surface of the module that is to contact the heatsink. The bottomsurface of the metal baseplate 3 is referred to as being “planar” and issaid to be “in a plane”, and it is planar and is in a plane in a generalsense, but it is to be understood that when considered in fine detailits center may actually have the above-described very slight convexdownward bow shape. The phraseology of a “planar bottom surface” that is“in a plane” is understood to describe both the perfectly planar exampleas well as the example that has the very slightly convex downward bowshape.

Solder-joined to the top surface of the metal baseplate 3 in the bottomof the tray is a semiconductor device assembly (not shown). Thesemiconductor device assembly, in the present example, includescircuitry involving at least one of the following components: a powerdiode, a power field effect transistor (MOSFET), a power insulated gatebipolar transistor (IGBT), a power thyristor. Covering this circuitryand assembly is a layer of an encapsulant (not shown), such as a layerof soft silicone gel material.

The power semiconductor device module 1 includes a plastic cap 4. Theplastic cap 4 is an injection molded plastic material piece. This cap 4fits down onto the upper rim of the tray, thereby covering theencapsulant and the open face of the tray. But for an arcuate indent ateach of its four corners 5, 6, 7 and 8, the cap 4 when considered fromthe top-down perspective of FIG. 3 has a rectangular shape. The cap 4has a row of peripheral holes. These holes form a peripheral ring ofholes that extends along the four peripheral side edges of the cap.

The power semiconductor device module 1 includes a plurality ofelectrical press-fit terminals or pins 9-41. Each of these electricalpress-fit terminals has a vertically extending press-fit pin portion anda wider lower base portion. The wider lower base portion includes alaterally extending wiring pad portion. The wiring pad portion issometimes called a “foot”. Each of these electrical press-fit terminalsis a stamped, formed and bent piece of sheet metal. An insertion machinepress fits the terminal down into an accommodating vertically-extendinginsertion channel in the plastic of the plastic housing frame 2. Theinsertion is done so that the channel holds the press-fit terminal inplace with respect to the housing frame. After the electrical press-fitterminals are inserted into selected ones of the accommodating channelsin plastic housing frame 2, the cap 4 is placed down over the electricalpress-fit terminals so that the vertically extending press-fit pinportions of the various electrical press-fit terminals extend up throughcorresponding ones of the peripheral holes in the cap. When the cap isin place, the press-fit pin portions of the electrical press-fitterminals extend upward and away from the cap in a directionperpendicular to the plane of the planar bottom surface of the metalbaseplate. There are fewer electrical press-fit terminals than there arechannel positions in the housing frame, and there are fewer electricalpress-fit terminals than there are peripheral holes in the cap.Accordingly, some of the channel positions and holes are not filled withelectrical press-fit terminals. There is no press-fit terminal extendingthrough some of the holes in the cap.

In one novel aspect, the power semiconductor device module 1 includesfour mechanical corner press-fit anchors 42-45. These four mechanicalcorner press-fit anchors 42-45 are disposed outside the rim of the traywhen the overall power semiconductor device module 1 is considered fromthe top-down perspective. None of the four mechanical corner press-fitanchors 42-45 is electrically connected to any circuitry disposed in thetray. Each of the four mechanical corner press-fit anchors 42-45 has alower barbed portion and an upper press-fit pin portion. The lowerbarbed portion secures the anchor to a cylindrical stand-off extensionof the housing frame 2 from which the anchor protrudes. The press-fitpin portion of the anchor extends upward and away from the housing frame2 in a direction perpendicular to the plane of the planar bottom surfaceof the metal baseplate. Mechanical corner press-fit anchor 42 isdisposed adjacent the corner 5 of the power semiconductor device module1. Mechanical corner press-fit anchor 42 is secured into, and extendsupwardly from, a cylindrical stand-off extension 46 of the plastichousing frame 2. Mechanical corner press-fit anchor 43 is disposedadjacent the corner 6 of the power semiconductor device module 1.Mechanical corner press-fit anchor 43 is secured into, and extendsupwardly from, a cylindrical stand-off extension 47 of the plastichousing frame 2. Mechanical corner press-fit anchor 44 is disposedadjacent the corner 7 of the power semiconductor device module 1.Mechanical corner press-fit anchor 44 is secured into, and extendsupwardly from, a cylindrical stand-off extension 48 of the plastichousing frame 2. Mechanical corner press-fit anchor 45 is disposedadjacent the corner 8 of the power semiconductor device module 1.Mechanical corner press-fit anchor 45 is secured into, and extendsupwardly from, a cylindrical stand-off extension 49 of the plastichousing frame 2. As can be seen from the top-down view of FIG. 3, eachof the mechanical corner press-fit anchors has a larger cross-sectionalarea (taken at the surface of the housing) as compared to the smallercross-sectional area of the electrical press-fit terminals (taken at thesurface of the cap).

Although the cylindrical stand-off extensions 46-49 in the specificexample illustrated are complete cylindrical structures, the cylindricalstand-off extensions in other examples are somewhat merged with the traysidewall portion of the remainder of the housing frame. Rather thanbeing cylindrical, the extensions can have an angular shape whenconsidered from the top-down perspective so long as enough plasticmaterial of the housing is provided to allow for the secure and strongattachment of the mechanical corner press-fit anchors to the housingframe.

The power semiconductor device module 1 is sold in this state with thepress-fit pin portions of the electrical terminals and the corneranchors extending upward from the top of the module, and without any ofthese press-fit pin portions being press-fit connected to any PCB.

A PCB has a set of plated through holes. There is one such hole for eachof the press-fit pin portions of the module 1. The plated through holesare arranged in the same pattern as are the upwardly extending press-fitpin portions of the module 1. As is known in the art, the plated throughhole of the PCB is slightly smaller than the press-fit pin portion thatis to go into the hole. Therefore, when the press-fit pin portion isforced into the hole, the press-fit pin portion and the metal of theplated through hole are forced together and form a cold weld. The holesfor the press-fit pin portions of the corner anchors 42-45 are largerthan the holes for the press-fit pin portions of the electricalpress-fit terminals. A special press tool is used to press the module 1into the PCB. In the illustrated embodiment, no screw or bolt is screwedinto the housing frame 2 in order to hold the module 1 to the PCB.

After the module has been press-fit attached to a PCB in this way, thenthe bottom surface of the power semiconductor device module 1 can beattached to a heatsink (not shown) using mounting holes 50-53. In oneexample, screws or bolts (not shown) are made to extend through theholes 50-53. As the screws or bolts are tightened, the metal baseplate 3of the module 1 is pulled against the heatsink so that the bottom of thebaseplate is in good thermal contact with the heatsink. There is onemounting hole located at each corner of the housing. The mounting holes50-53 are unthreaded.

FIG. 4 is a diagram of one example of mechanical corner press-fit anchor45. The anchor 45 is inserted into an axial hole in the cylindricalstand-off extension 49 of the housing frame 2 so that the lower portion54 of the anchor 45 sticks down into an axial hole in cylindricalstand-off extension 49 and so that the upper press-fit pin portion 55sticks out of the housing frame 2 as shown in FIG. 1. Stand-offextension 49 is cylindrical in this example, but in other examples thestand-off extension can be of other shapes. Barbs or catches 56 and 57dig into the resilient plastic polymer material of the inside walls thehole. Due to the barbs 56 and 57, a substantial pull out force can beput on the anchor without the anchor moving with respect to the housingframe. This pull out force is referred to here as the “anchor pull outresist force”. Under this force, the anchor remains at the same locationin its hole in the housing frame. An individual electrical press-fitterminal has a rated minimum pull out extraction force at which theelectrical press-fit terminal is specified to be extractable from a PCBto which the electrical press-fit terminal has been press-fit attached.In one example, the anchor pull out resist force of one of the anchors42-45 is a force that exceeds the rated minimum pull out extractionforce with which an electrical press-fit terminal is specified to beextractable from a PCB.

FIG. 5A is a diagram of a first example 35A of electrical press-fitterminal 35. The lower portion 58 of the terminal has a laterallyextending landing pad portion 59. The upper press-fit pin portion 60 ofthis terminal is of the “eye-of-the-needle” type.

FIG. 5B is a diagram of a second example 35B of electrical press-fitterminal 35. The lower portion 61 of the terminal has a laterallyextending landing pad portion 62. The upper press-fit pin portion 63 ofthis terminal is of the “fork” type.

FIG. 5C is a diagram of a third example 35C of electrical press-fitterminal 35. The lower portion 64 of the terminal has a laterallyextending landing pad portion 65. The upper press-fit pin portion 66 ofthis terminal is of the “post” type.

FIG. 6 is a cross-sectional side view of an assembly involving the powersemiconductor device module 1 of FIG. 1. The diagram is illustrative andis not to scale. The areas of the bolts 69 and 70 are shown incross-section whereas the center part of the diagram shows the assemblyfrom the side. The top side of the power semiconductor device module 1is press-fit attached to the bottom side of a PCB 67. Each of thepress-fit pin portions of the electrical press-fit terminals and each ofthe press-fit pin portions of the mechanical corner press-fit anchors isforced into a corresponding plated-through hole in the PCB. A finnedmetal heatsink 68 is attached to the backside surface of the baseplate 3and is held in place by four bolts, including the two bolts 69 and 70pictured. There are four holes in the PCB, one for each of the fourbolts. Each bolt is inserted downward through its corresponding hole inthe PCB. Each bolt sticks through its corresponding hole in the module(one of unthreaded mounting holes 50-53), and then threads into acorresponding threaded hole in the heatsink 68. The inside of themounting hole is actually a metal collar extension portion of thebaseplate. As the bolt is tightened, the bottom of the head of the boltcontacts the top of the collar extension portion. As the bolt is rotatedfurther, the heatsink is drawn up toward the bottom surface of thebaseplate of the module. The bolts are torqued down to press theheatsink to the bottom of the baseplate of the module.

Conventionally in the art, special press equipment is used to press theprior art module 100 of FIG. 7 into a PCB so that the press-fit pins ofthe module are forced into their respective plated through-holes of thePCB in the proper way. The press equipment measures force versus time.Based on the force and time measurements, the press equipment determineswhen to stop forcing the module into the PCB. The determination of whento stop is an indirect measure of cold weld quality. The determinationof when to stop is not made based on how far the top surface of themodule is from the PCB. Sometimes the press equipment stops the pressingoperation when there are still separations between the tops of thecylinder stand-off extensions 111-114 (also sometimes called “domes” or“mounting stand-offs”) of the housing frame 110 and the PCB. Other timesthe press equipment stops the pressing operation when there is noseparation between the tops of the cylinder stand-off extensions 111-114and the PCB. Sometimes a cylinder stand-off extension at one corner ofthe module is left contacting the PCB but another cylinder stand-offextension at another corner of the module is left with space between thetop of that cylinder stand-off extension and the PCB. The finalpositions of the press-fit pins in their respective holes in the PCB canbe different in the various corners of the same module, and can bedifferent from module to module.

After the pressing equipment has been used to force the press-fit pinsof the prior art module 100 into the PCB, the press-fit pins are leftcold welded to the metal of their respective plated through-holes. Next,in what is usually a manual process, self-tapping screws or bolts arescrewed down through holes in the PCB and into axial holes in thecylindrical stand-off extensions 111-114. The head of a screw on the topof the PCB forces down onto the PCB with respect to the module so thatthe screw head holds the PCB down onto the module. Such a screw hasthreads. As the screw is screwed into the hole, these threads in aself-tapping fashion cut into the soft polymer plastic material of theinside wall of the cylindrical stand-off extension. As a result, thescrews once installed are not easily pulled out. This allows the screwsto withstand a desired amount of pullout force. When the rotation ofsuch a screw or bolt is stopped during installation is determined basedon the turning torque reaching a detected maximum. It has beendetermined that due to the potential separation between the tops of thecylindrical stand-off extensions 111-114 of the housing frame 110 andthe PCB, the application of these screws or bolts sometimes imparts anundesirable amount of mechanical stress on the PCB. Sometimes theapplication of a screw or bolt leaves the PCB pulled and warped downwardtoward the module in the locale of the screw or bolt head. This warpage,and the associated mechanical stress, can cause various types offailures. The novel mechanical corner press-fit anchors 42-45 describedabove in connection with FIGS. 1-3 overcome these problems by dispensingwith the screws or bolts. The mechanical holding function of the priorart screws or bolts is fulfilled by the mechanical corner press-fitanchors 42-45. The press equipment inserts the press-fit pin portions ofthe mechanical corner press-fit anchors into corresponding platedthrough-holes in the PCB in the same way, and at the same time, that itinserts the press-fit pin portions of the electrical press-fit terminalsinto their corresponding plated through-holes. The mechanical corneranchors do not have heads. As a result, the PCB is not left in a warpedcondition with screw or bolt heads pulling down and warping the PCBdownward toward the module. In addition, the expense and delay of theextra manual step of applying the screws or bolts, and using the torquedriver, is avoided.

Although certain specific embodiments are described above forinstructional purposes, the teachings of this patent document havegeneral applicability and are not limited to the specific embodimentsdescribed above. The press-fit portion of the mechanical cornerpress-fit anchor can be of any suitable style of press-fit pin,including a forked style pin or a so-called eye-of-the-needle style pin,and need not be a post pin style press-fit pin. The lower portion of amechanical press-fit anchor need not have any barb or catch, but rathercan be of a smooth and regular cylindrical shape or a smooth and regularbar shape as long it is has enough frictional attachment to the plasticof the housing frame to provide the necessary anchor pull out resistforce. Many other suitable ways of attaching the press-fit pin portionof an anchor to the housing frame are possible. A mechanical cornerpress-fit anchor may have a threaded lower portion so that the threadedlower portion can be screwed down into the hole in a cylindricalstand-off extension. In one example, the same terminal insertionequipment that automatically inserts the electrical press-fit terminalsinto corresponding channels in the housing also inserts the mechanicalcorner press-fit anchors. Accordingly, various modifications,adaptations, and combinations of various features of the describedembodiments can be practiced without departing from the scope of theinvention as set forth in the claims.

What is claimed is:
 1. A power semiconductor device module comprising: ametal baseplate; a housing frame formed of an electrically insulativematerial, wherein the housing frame and the metal base plate fittogether to form a shallow tray with an upper rim; a cap formed of anelectrically insulative material disposed on the upper rim, the caphaving a plurality of peripheral holes formed therein; a plurality ofelectrical press-fit terminals, wherein each electrical press-fitterminal extends through a corresponding one of the peripheral holessuch that a press-fit pin portion of the electrical press-fit terminalextends upward and away from the cap in a direction perpendicular to aplanar bottom surface of the metal baseplate; and a plurality ofmechanical corner press-fit anchors disposed outside the upper rim,wherein each of the mechanical corner press-fit anchors has a press-fitpin portion that extends upward and away from the housing frame in adirection perpendicular to the planar bottom surface of the metalbaseplate.
 2. The power semiconductor device module of claim 1, whereinno press-fit pin portion of any of the plurality of electrical press-fitterminals is press-fit connected to any printed circuit board, andwherein no press-fit pin portion of any of the four mechanical cornerpress-fit anchors is press-fit connected to any printed circuit board.3. The power semiconductor device module of claim 2, wherein eachpress-fit pin portion of each of the electrical press-fit terminals hasa shape taken from the group consisting of: a post shape, a fork shape,and an eye-of-the-needle shape, and wherein each press-fit pin portionof each of the mechanical corner press-fit anchors has a shape takenfrom the group consisting of: a post shape, a fork shape, and aneye-of-the-needle shape.
 4. The power semiconductor device module ofclaim 2, wherein none of the mechanical corner press-fit anchors iselectrically connected to any circuitry disposed in the powersemiconductor device module.
 5. The power semiconductor device module ofclaim 2, wherein each of the press-fit pin portions of each of theelectrical press-fit terminals has a first cross-sectional area taken ina plane at a top surface of the power semiconductor device module,wherein each of the press-fit pin portions of each of the mechanicalcorner press-fit anchors has a second cross-sectional area taken in aplane at a top surface of the housing frame, wherein the secondcross-sectional area is greater than the first cross-sectional area. 6.The power semiconductor device module of claim 2, wherein the cap has asubstantially rectangular shape when the power semiconductor devicemodule is considered from a top-down perspective, and wherein theplurality of peripheral holes forms a peripheral ring of holes thatextends along four peripheral edges of the cap when the powersemiconductor device module is considered from the top-down perspective.7. The power semiconductor device module of claim 2, wherein the housingframe has four cylindrical extension portions, and wherein eachrespective one of the four mechanical corner press-fit anchors extendsfrom a corresponding one of the four cylindrical extension portions. 8.A power semiconductor device module comprising: a metal baseplate,wherein a bottom surface of the metal baseplate is disposed in a plane;a housing frame formed of an electrically insulative material, whereinthe housing frame engages the metal baseplate such that the metalbaseplate and the housing frame together form a tray, wherein the trayhas a rim; a cap formed of an electrically insulative material disposedon the rim, thereby covering the tray; a plurality of electricalpress-fit terminals, wherein a press-fit pin portion of each electricalpress-fit terminal extends upward and away from the cap in a directionperpendicular to the plane of the bottom surface of the metal baseplate;a plurality of mechanical corner press-fit anchors, each having a lowerportion that extends into the housing frame, wherein each of themechanical corner press-fit anchors also has a press-fit pin portionthat extends out of the housing frame in a direction perpendicular tothe plane of the planar bottom surface of the metal baseplate; and powerelectronics disposed in the tray, wherein the power electronics areelectrically coupled to each of the electrical press-fit terminals,wherein the power electronics include at least one component taken fromthe group consisting of: a power diode, a power field effect transistor,a power insulated gate bipolar transistor, and a power thyristor.
 9. Thepower semiconductor device module of claim 8, wherein each of themechanical corner press-fit anchors is secured to the housing frame. 10.The power semiconductor device module of claim 8, wherein each of thelower portions of the mechanical corner press-fit anchors engages thehousing frame in a manner that prevents the mechanical corner press-fitanchors from being pulled out of the housing frame under an anchor pullout resist force, wherein the anchor pull out resist force is a forcegreater than a minimum pull out extraction force at which one of theelectrical press-fit terminals can be disengaged from a printed circuitboard were the electrical press-fit terminal to have been press-fitmounted to the printed circuit board.
 11. The power semiconductor devicemodule of claim 8, wherein each of the lower portions of the mechanicalcorner press-fit anchors engages the housing frame such that under ananchor pull out resist force the mechanical corner press-fit anchors donot move away from the housing frame in a direction perpendicular to theplane of the bottom surface of the metal baseplate.
 12. The powersemiconductor device module of claim 8, wherein each of the press-fitpin portions of the electrical press-fit terminals has a firstcross-sectional area taken in a plane at a top surface of cap, whereineach of the press-fit pin portions of the mechanical corner press-fitanchors has a second cross-sectional area taken in a plane at a topsurface of the housing frame, wherein the second cross-sectional area isgreater than the first cross-sectional area.
 13. An assembly comprising:a power semiconductor device module comprising: a metal baseplate,wherein a bottom surface of the metal baseplate is disposed in a plane;a housing frame formed of an electrically insulative material, whereinthe housing frame engages the metal baseplate, wherein the housing frameat least in part forms a tray; a cap formed of an electricallyinsulative material that covers the tray; a plurality of electricalpress-fit terminals, wherein each electrical press-fit terminal has apress-fit pin portion that extends away from the cap in a directionperpendicular to the plane of the bottom surface of the metal baseplate;and a plurality of mechanical corner press-fit anchors, wherein each ofthe mechanical corner press-fit anchors has a lower portion that extendsinto the housing frame, and wherein each of the mechanical cornerpress-fit anchors also has a press-fit pin portion that extends awayfrom the housing frame in a direction perpendicular to the plane of theplanar bottom surface of the metal baseplate; and a printed circuitboard, wherein the press-fit pin portions of the electrical press-fitterminals and the press-fit pin portions of the mechanical cornerpress-fit anchors are press-fit connected to the printed circuit board.14. The assembly of claim 13, further comprising: a heatsink that ismounted to the power semiconductor device module so that the heatsink isin thermal contact with the bottom surface of the metal baseplate. 15.The assembly of claim 13, wherein each of the press-fit pin portions ofeach of the electrical press-fit terminals has a first cross-sectionalarea taken in a plane at a top surface of cap, wherein each of thepress-fit pin portions of each of the mechanical corner press-fitanchors has a second cross-sectional area taken in a plane at a topsurface of the housing frame, wherein the second cross-sectional area isgreater than the first cross-sectional area.
 16. The assembly of claim13, wherein all of the mechanical corner press-fit anchors are disposedoutside the cap when the power semiconductor device module is consideredfrom a top-down perspective looking down onto the cap.
 17. The assemblyof claim 13, wherein the lower portion of each of the mechanical cornerpress-fit anchors engages the housing frame such that under an anchorpull out resist force it does not move away from the housing frame in adirection perpendicular to the plane of the bottom surface of the metalbaseplate, wherein the anchor pull out resist force is a force greaterthan a minimum pull out extraction force at which one of the electricalpress-fit terminals can be disengaged from a printed circuit board werethe electrical press-fit terminal to have been press-fit mounted to theprinted circuit board.
 18. The assembly of claim 13, wherein the powersemiconductor device module further comprises power electronics disposedin the tray, wherein the power electronics are electrically coupled toeach of the electrical press-fit terminals, wherein the powerelectronics include at least one component taken from the groupconsisting of: a power diode, a power field effect transistor, a powerinsulated gate bipolar transistor, and a power thyristor.
 19. Theassembly of claim 13, wherein the housing frame has extension portions,and wherein each of the mechanical corner press-fit anchors extends froma corresponding one of the extension portions.
 20. A power semiconductordevice module, wherein the power semiconductor device module has abottom surface and has a rectangular shape when considered from atop-down perspective, the power semiconductor device module comprising:a metal baseplate, wherein a planar bottom surface of the metalbaseplate is the bottom surface of the power semiconductor devicemodule; a housing frame of an insulative plastic material, wherein thehousing frame is disposed with respect to the metal baseplate such thatthe metal baseplate and the housing frame together form a shallow tray;power electronics disposed in the shallow tray, wherein the powerelectronics includes at least one component taken from the groupconsisting of: a power diode, a power field effect transistor, a powerinsulated gate bipolar transistor, and a power thyristor; a cap of aninsulative plastic material that fits down onto the housing framethereby enclosing the power electronics in the shallow tray; a pluralityof electrical press-fit terminals, wherein each electrical press-fitterminal extends upward in a direction normal to the planar bottomsurface of the metal baseplate, wherein each of the electrical press-fitterminals has a first cross-sectional area; and a plurality ofmechanical press-fit anchors, wherein each of the mechanical press-fitanchors extends upward in a direction normal to the planar bottomsurface of the metal baseplate, wherein none of the mechanical press-fitanchors is electrically coupled to any other one of the mechanicalpress-fit anchors, wherein none of the mechanical press-fit anchors iselectrically coupled to any of the electrical press-fit terminals,wherein each of the mechanical press-fit anchors has a secondcross-sectional area, and wherein the second cross-sectional area islarger than the first cross-sectional area.